Process for producing fruit flakes or wafers, and fruit flakes or wafers produced in accordance therewith

ABSTRACT

Fruit flakes made by applying a moist mass of fruit pulp, sugar and starchy material to a hot smooth substrate in a thin layer, at least partially dehydrating said layer to form a cohesive film, peeling said film from said substrate and forming said film into an irregular structure, drying said film until it is brittle, and dividing said film into flakes.

This is a Rule 60 Continuation Application of co-pending Ser. No.432,711 filed Jan. 11, 1974 now abandoned, the priority of which ishereby claimed, which itself claimed the priority of German applicationP 23 02 242.6 filed on Jan. 18, 1973.

The invention concerns a process for producing fruit flakes or fruitwafers from fruits. Especially preferred are oranges, apricots,pineapples, bananas and guavas. The invention further concerns fruitflakes or wafers produced from such fruits according to this or to anequivalent process.

The invention is based on the need for a process which makes it possibleto produce fruit flakes or wafers relatively simply and cheaply and ingreat quantities, and which will provide products that are both tastyand nutritious.

This problem is solved according to this invention by utilizing a moist,practically homogeneous mass of material, which consists essentially offruit pulp or the like, with sugar or sugar-like materials added, and ofstarchy substances, especially cereals, such as, for example, corn meal.This mass is applied to a hot smooth substrate in at least onerelatively thin layer. Through dehydration, it is brought to thecohesive, malleable or thermoplastic state. It is then peeled off thehot substrate. Preferably simultaneously or shortly afterwards, it iscontinuously packed, compressed, or restrained, and/or, if necessary,pulled or tugged, in such a way that the material preferably attains anirregular, corrugated, knurled, or waffle-like structure, with varyingthicker and thinner thicknesses. The film with this structure is thencooled, completely dried, and finally cut into pieces or divided intomore or less regularly shaped flakes or wafers.

The invention brings to the market a new foodstuff and delicacy, at aprice that can be afforded by all. As a pure, vitamin containing,natural product, it has high nutritional value, and can be used byitself or as a frequent additive for various dishes. As a consequence oftheir special structure, which is due to the invention, the fruit flakesremain loose and crunchy during storage and use, look appealing, tastepleasantly tart and very fruity, and are free of harmful components orimpermissible foreign additives.

Fresh fruits, as well as pasteurized or frozen ones, can be used as rawmaterial, in the form of fruit pulp, fruit puree, strained andhomogenized fruits. By the expression "fruit pulp", these and similarforms of fruit mass are intended to be covered. Corn meal or any similarproduct is preferred as starch additive, because of its attractive priceand because of its special suitability for the purposes of theinvention. The general designation "sugar" designates beet sugar as wellas cane sugar, as well as molasses, glucose, etc. In the processaccording to the invention, a caramelizing effect is important for themass of material.

As an example of the preferred form of the invention, the composition ofthe moist mass contains about 80 - 85% fruit pulp or the like, 5 - 10%sugar or the like, and 5 - 10% starchy material, such as cereals or thelike, in weight percent. The weight ratio of moist material to drymaterial is preferably about 3 : 1. Thus, for example, 300 kg moistmaterial yield about 100 kg dry material. It should further be notedthat, under some circumstances, the addition of special ingredients,such as taste improving materials, vitamins, spices, etc. is possible,without any change in the basic composition of the material mass.

In particular, the process according to the invention can be performedin several variants. The moist material mass, for example, can beapplied to a smooth flat substrate. But for practical manufacture, arotating heated drying drum or drying cylinder is preferred. The moistmaterial mass comes from a storage or mixing container, and is appliedto this drying cylinder at one or more sites, and is evenly distributed.For this purpose, one or more sequentially arranged application rollers,which are in themselves well-known, are used. The width of the dryingcylinder is chosen arbitrarily. For example, it can be 2.50 m. If two ormore application rollers are provided, fresh material mass is applied infront of each application roller and is distributed over the width ofthe drying cylinder. The drying cylinder is advantageously heated bysaturated steam, which is introduced through the interior of thecylinder. The steam is at a pressure of 4 - 6 atmospheres, and theattained temperature ranges for 110° to 140° C. Vapors formed from thematerial mass during desiccation are pumped off with a suitable device.The film of material on the drying cylinder has a thickness of about 1 -2 mm.

The film of material which forms on the drying cylinder rotates with thecylinder surface about a circumferential angle of typically 270°,whereby moisture is withdrawn from it to an ever increasing degree.While the film of material is still in a malleable or thermoplasticstate, it is peeled off the drying cylinder by means of a scraping knifewith a pointed blade, which is pressed against the cylinder surface.From the scraping knife, it then traverses a relatively short distancein the opposite direction, which is preferably 16 - 20 mm. long. Thisdistance is traversed free, that is, without any support. It thenreaches a smooth sheet metal guide, which is suitably inclined, andwhich ends at a short distance from the surface of the drying cylinder.The film of material is guided in this way to a running transport beltwhich carries it along. The transport belt consists, for example, of anendless wire mesh, or is provided with some other rough surface so as tobe able to pull along the film.

In the region where the hitherto smooth film of material is peeled off,that is shortly before, on, and behind the scraping knife, and even onthe subsequent sheet metal guide, continuous packing, compression,restraint, and/or, if necessary, pulling and stretching takes place.This results in the formation of the characteristic structure of fruitflakes, in accordance with the invention. The structure has the form ofa preferably irregular corrugation, knurling, or waffle-like shape, withalternating thicker and thinner thicknesses. This structure begins toappear at the scraping knife and at the subsequent free path betweenscraping knife and sheet metal guide. Its formation, however, oftenstill continues while the film of material is moved from the sheet metalguide to the transport belt. Air is blown over the entire width of thefilm of material, underneath the peeled-off film and between the filmand the sheet metal guide. The air is obtained, for example, from an airnozzle.

The structure formation in the film of material can be varied by varyingthe circumferential speed of the drying cylinder and the running speedof the transport belt. Braking the run-off speed will cause compressionof the material while increasing this speed will stretch the film. Thematerial film also depends, among other factors, on the effect of thesugar content and of caramelization. It should be noted that the processcan, if desired, also be performed in vacuum.

Further drying of the structured material film may occur on thetransport belt, and can generally be performed at normal roomtemperature. Normally, at approximately the end of the first third ofthe entire length of the transport belt, the material is substantiallycompletely dry. Up to the end of the conveyor belt, the material usuallyhas been running along in its full width. At this point it may be cutinto lengthwise strips of adjustable width, and divided, eithersimultaneously or subsequently, in the perpendicular direction, to formflakes or wafers of the desired size. This can be done, for example,especially simply by pushing the film strip of material beyond the endof the transport belt, so that it protrudes freely, until its own weightor some external force causes it to break off and fall down. Thisessentially completes the fabrication process, and the dry, crispy fruitflakes or wafers can be gathered, transported, and packed.

While only a limited number of embodiments have been expresslydisclosed, the invention is, nonetheless, to be broadly construed andnot to be limited except by the character of the claims appended hereto.

What is claimed is:
 1. A process for the production of fruit flakescomprising applying a moist mass consisting essentially of fruit pulp,sugar added to said pulp and starchy material added to said pulp, to ahot smooth rotating cylindrical substrate in a thin layer, said fruitpulp being about 80 to 85 percent by weight of said moist mass, saidadded sugar being about 5 to 10 percent by weight of said moist mass andsaid added starchy material being about 5 to 10 percent by weight ofsaid moist mass, maintaining the substrate at a temperature sufficientto cause caramelization of said moist mass, at least partiallydehydrating said layer to form a cohesive film, peeling said film fromsaid substrate and forming said film into an irregular structure, dryingsaid film until it is brittle, and dividing said film into flakes.
 2. Aprocess according to claim 1 wherein said forming comprises pulling,pushing, compressing; restraining or stretching said film as it is beingremoved from said substrate whereby said film is corrugated, curled orwaffled with varying thicknesses.
 3. A process according to claim 1wherein said substrate is heated to 110° to 140° C.
 4. A processaccording to claim 3 wherein said substrate is heated by saturated steamat about 4 to 6 atmospheres.
 5. A process according to claim 1 whereinvapors formed during said dehydrating are pumped off.
 6. A processaccording to claim 1 wherein said peeling is carried out by a scrapingknife.
 7. A process according to claim 1 comprising causing said film tofreely traverse a relatively short path after leaving said substrate. 8.A process according to claim 7 wherein said short path is approximately16 to 20 mm.
 9. A process according to claim 7 wherein, after freelytraversing said path, said film is placed on a moving support and air isblown underneath said film.
 10. A process according to claim 7 whereinthe speed of said support and the speed of said peeling are differentwhereby said film is compressed or stretched.
 11. A process according toclaim 1 wherein said film after said dehydrating is cut lengthwise anddivided crosswise into flakes.
 12. A process according to claim 9wherein said film is pushed over the end of said support so as toprotrude freely, permitting said film to break off in the form offlakes.
 13. A process according to claim 1 wherein said film is 1 to 2mm. thick while on said substrate.
 14. A process according to claim 1wherein said mass has a weight ratio of wet material to dry material ofabout 3 to
 1. 15. A process according to claim 1 wherein said masscontains 80 to 85% pulp, 5 to 10% added sugar and 5 to 10% added starchymaterial, all percents being by weight.
 16. A process according to claim1 carried out under vacuum.
 17. A process according to claim 1 whereinsaid starchy material is corn meal.
 18. Fruit flakes consistingessentially of a dried mass of fruit pulp, added sugar, added starchymaterials and having an irregular, corrugated, knurled, or waffledstructure with varying thicknesses.